Rudrayamala Tantra
The Rudrayamala is used as a source by many other agamas but the original appears to be lost. Strictly speaking, a Yamala is a different class of text, and supposed to pre-date the tantras. However, manuscripts of the Yamala seem to be lost, except as quotations in later works.
This analysis of the contents is of a tantra given the same name, but almost certainly, from internal evidence, not the original text. Although its provenance is unknown, it nevertheless contains a great deal of interesting information and focuses in great detail on the identity of the goddess with Kundalini. Published in a Sanskrit edition by the Vacasampati Press, Calcutta, this work is divided into 66 chapters (patala) of different lengths and written in a simple manner.
In Sanskrit > यामला => Yaamala (means)
Pair /Couple /Twins
Many Yaamala Texts are there
Sri Yaamala /Vishnu Yaamala /Shakti Yaamala /Brahma Yaamala /Rudra Yaamala
Of these The Rudra Yaamala is very famous ,because it contains -an Elaborate description of the KUNDALINI YOGA
The ORIGINAL Rudra Yaamala is Extinct —Redaction are there -
But the original is Almost available,
because Many Separate Portions of Rudra Yamala are there in many other Texts.